There is already a name for this .. the schmoo.
This borders on the silly things rich folks who do not understand science (aka Bill Gates for this one) spend money on.
First, to be truly free of animal sources, the medium used to grow the cells that make this meat would need to be artificial. Cell culture normally uses serum .. made by cows. Perhaps Memphis meats buys serum cheap now but imagine the price when they scale up!
Replacing that would be a yuge task and likely inefficient.
Second to mimic chemical composition, aka taste, the in vitro grown meat would require homophones .. again most of these need to be made by cells, themselves grown in culture. Third, the cultures themselves are hugely energy inefficient. They require heat and gases .. O2 esp. They also produce CO2.
Third, animals have evolved elaborate safety mechanism ..e.g. the immune system .. that protects them (and us) from bad things like viruses. FDA regulatory systems would be, shall we say, stretched beyond bureaucratic limits of asked to approve cultures meat. Hell, I do to eat talapia from Chines fish farms and worry about farm grown shrimp from Thailand. And these guys expect me to eat meat grown in a factory???
It is likely a lot easier to build a GMO animal designed to generate less CO2 and methane , leave less feces, make a meat that is kosher and hallal, and (of course) sacrifice itself on command. There is already a name for this .. the schmoo. Of course the schmoo would need hooves and a cow stomach to qualify as kosher!